Control panel displays E02 and heating stops

Safety first: Disconnect power from the spa before touching the pump/heater unit or opening any covers.

• Power cycle: Unplug the spa for 10–15 minutes to allow the control board to fully discharge, then plug back in and check if E02 clears.
• Check water temperature: Use an external thermometer to verify actual water temperature. If the reading is normal but the spa shows an extreme value or E02, the sensor is likely faulty.
• Inspect sensor cable:
  • Locate the temperature sensor cable running from the heater tube into the control housing.
  • Check for cuts, abrasions, or melted insulation.
  • Gently wiggle the connector at the control board (with power off) to ensure it is fully seated.
• Dry any condensation: If the control housing is damp, dry it thoroughly with a cloth and allow it to air dry before reconnecting power.

If E02 persists, the NTC temperature sensor or the main control PCB will likely need replacement. This repair involves opening the sealed control housing and should be done by a qualified service technician to maintain safety and water-tight integrity.